package com.chj.chuji.tijie14;

//https://blog.csdn.net/m0_37579232/article/details/81259629
//https://blog.csdn.net/westbrook1998/article/details/81301840
//https://blog.csdn.net/V5ZSQ/article/details/82917220
public class Partition {
	public static void main(String[] args) {
		int n = 5;
		int sum = (n * (n - 1)) / 2;
		System.out.println(sum);
	}
}
